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Discussion Starter #1
2003 Silverado 1500

For the last couple of months, just randomly while driving, all of my dash gauges and warning lights would go off, and immediately come back on. Just like they would do when you first turn the key to the power on position while starting the engine. But the truck never died, radio stayed on, A/C etc.

Fast forward to yesterday morning. I left the trick running and went in the gas station, I came out and got in to leave and all of a sudden the truck died. It will turn over but will not start. After a bit I notice that Now not only are all the dash lights and gauges failing to come on when the key is turned, but also the fuel pump isn’t getting any power. I thought it sounded like the ignition switch had went bad so I replaced it yesterday afternoon with no luck. I’ve also checked every fuse I could possibly think of that may be related, anything pcm, ign, etc. I’ve also swapped all the relays around with known good ones. No luck.

I thought maybe I had gotten a bad ignition switch from the parts house so I tested the wires coming and going from it as well. While in the “On” position all read 12v except the yellow “engine crank” wire, as they should.

The only thing on the dash is the check engine light is illuminated. However it wasn’t throwing a code on my OBD2 reader. I then out of curiosity unhooked the TPS to check for 5v there, which it had. After that the OBD2 reader showed some TPS faults so I know the reader is working. Cleared those and rechecked and had zero codes. Check engine light still illuminated.

I need some input guys. Sorry for the long post
 

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2003 Silverado 1500

For the last couple of months, just randomly while driving, all of my dash gauges and warning lights would go off, and immediately come back on. Just like they would do when you first turn the key to the power on position while starting the engine. But the truck never died, radio stayed on, A/C etc.

Fast forward to yesterday morning. I left the trick running and went in the gas station, I came out and got in to leave and all of a sudden the truck died. It will turn over but will not start. After a bit I notice that Now not only are all the dash lights and gauges failing to come on when the key is turned, but also the fuel pump isn’t getting any power. I thought it sounded like the ignition switch had went bad so I replaced it yesterday afternoon with no luck. I’ve also checked every fuse I could possibly think of that may be related, anything pcm, ign, etc. I’ve also swapped all the relays around with known good ones. No luck.

I thought maybe I had gotten a bad ignition switch from the parts house so I tested the wires coming and going from it as well. While in the “On” position all read 12v except the yellow “engine crank” wire, as they should.

The only thing on the dash is the check engine light is illuminated. However it wasn’t throwing a code on my OBD2 reader. I then out of curiosity unhooked the TPS to check for 5v there, which it had. After that the OBD2 reader showed some TPS faults so I know the reader is working. Cleared those and rechecked and had zero codes. Check engine light still illuminated.

I need some input guys. Sorry for the long post
On this generation it’s very common for a bad ground to cause this kind of problem. I’ve had similar behavior myself. I’d start by identifying all the grounds you can find and cleaning them up. It’s also possible you have a bad gauge cluster, but I’d be chasing grounds first.
Good luck!
 

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Thanks for the input. I guess I’ll start looking at grounds tomorrow. No clue how many or where to start though. All info is very much appreciated.
 

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Thanks for the input. I guess I’ll start looking at grounds tomorrow. No clue how many or where to start though. All info is very much appreciated.
I have a link, but it’s for another forum. Nono... if you search for NBS ground locations, I’m sure you’ll find the goods.
 

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Run a new wire from the negative post on the battery to the fender this will eliminate any body ground issues, also there is a ground near the starter. Definitely check the fuel pump to frame ground. You can see it with a flashlight where the wires come out of the pump I've had that one go bad myself
 

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Had same problem with gauges randomly not working. Finally sent it to GM Gauge Repair in WI and had him go thru it and add new LEDs while he was repairing it. Fixed the gauge issue. As previously stated, check the grounds for the fuel issue
 
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There's a ground wire on your spare tire mounting plate. Check that out. I had to put a new connector, shine up some frame with a wire wheel, and use a self tapping screw. All good now!
 

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There's a ground wire on your spare tire mounting plate. Check that out. I had to put a new connector, shine up some frame with a wire wheel, and use a self tapping screw. All good now!
I’ll have to check this too! Never knew there was one back there..
 
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